Method For Estimating Improved Potential Of Cultivated Land Quality Based On Land Consolidation Project In Hilly Areas

The quality construction of cultivated land is the key content of the land consolidation in China,and estimating quality-improvement potential of cultivated land is the foundation of cultivated land quality construction.It is of great significance to improve the quality of cultivated land,improve ecological environment and ensure food security in hilly areas.With the improvement of the position and function of land consolidation in China,the essence of land consolidation has become the sustainable development of "Sansheng" space by adjusting the relationship between people and land.This requires that land consolidation should be oriented to the regional function,definite the position of the area,carry out the differential land rectification.The terrain of southwest hilly areas is big,the economic development is unbalanced,soil erosion,geological disaster and other ecological problems are serious,and the different land consolidation is more necessary.However,the study of cultivated land quality potential is more ideal.They usually direct the highest level in the area as the target of cultivated land quality improvement to calculate the potential.The objective setting of this method is not scientific enough to consider the regional function and site conditions,so the scientific and feasible method of calculation needs more scholars to study.This paper chooses Chongqing Qijiang District as Research area.Firstly,the paper uses the method of "Sansheng" function index and system cluster analysis to divide the land consolidation areas,and puts forward the corresponding consolidation direction,which provides scientific basis for the goal setting and potential calculation of cultivated land quality improvement.Secondly,based on the existing evaluation system of cultivated land quality,this paper analyzes the influence of land remediation engineering measures on the quality of cultivated land in hilly areas,and puts forward a set of methods to calculate the cultivated land quality improvement.Finally,Accurate identify the improvement factors of land improvement,determine the goal of improvement according to the regional functional characteristics and site conditions,and the potential of cultivated land quality improvement was calculated.Through the analysis of the core factors of the quality of cultivated land,the key projects of land consolidation are determined.The aim is to provide reference for the estimation of cultivated land quality potential in the hilly areas of southwest China.The main findings are as follows:(1)The terrain is complex and the three-dimensional structure is obvious in hilly areas."Sansheng" function-oriented zoning of land remediation is the basis for the measurement of quality-improvement potential of cultivated land.The site condition index,production function index,life function index and ecological function index of each town street were calculated by multifactor comprehensive evaluation method,and the functional index of production,living and ecology varied with the site conditions.Taking Qijiang District in Chongqing as the study area,an empirical research was conducted to practice the land consolidation zoning method through comprehensive evaluation of functional index and systematic cluster analysis.Combining the results of clustering and the actual situation,the study area was divided into 4 land remediation zones,followed by the corresponding strategies.In the Urban-rural Integrated Development Zone,the development intensity should be controlled and the space of production,living and ecology should be optimized.Industrial Transformation Oriented Zone should focus on accelerating industrial restructuring and upgrading and coordinating the relationship between industrial development and environmental protection.In Agricultural Land Remediation Oriented Zone,high standards basic farmland construction should be attached much importance to promote the modern agricultural development.Mountain ecological protection oriented zone should concentrate on strengthening the Ecological system construction and promoting key scenic spots.It is of significance for regional land consolidation project layout and project implementation.It is helpful for clarifying the goal and focus of land consolidation in hilly areas,providing scientific basis for the goal setting and potential calculation of cultivated land quality improvement,and of significance for regional land consolidation project layout and project implementation.(2)In this paper,a set of cultivated land quality evaluation and potential measurement methods are established to serve the land consolidation in hilly areas.Based on the existing index system of cultivated land quality evaluation,combining with the influencing factors for cultivated land quality of land consolidation engineering measures in hilly areas,the paper constructed the evaluation Index system,and formed a method of evaluating cultivated land quality and estimating its potential in hilly areas serving land consolidation,referring to the method system of farmland grading.The quality of cultivated land in the study area was 9.79,and the correlation between the cultivated land use index and actual yield of the converted base crops(R2=0.8950)was greater than that among agricultural land classification(R2=0.7974),which indicated that the quality of cultivated land was closer to the actual situation.The method realizes the comparability of the quality evaluation results before and after the land renovation,improves the accuracy of evaluating the quality of cultivated land in mountainous and hilly area,and has strong practicability.(3)This study accurately identifies the improvement factors of land consolidation and scientifically designs the lifting scheme.The potential of cultivated land is relative,and it depends on the current situation and the target of consolidation.Through the analysis of the improvement factors of cultivated land quality,the goal of consolidation was determined,according to the characteristics of the functional area and site conditions.The quality of cultivated land was improved by 0.81 in average.The areas of high potential,middle potential and low potential area accounted for 35.86%,28.97% and 35.17% respectively.The cultivated land quality potential distribution in space showed more heterogeneity.It avoids the pattern of "the worse the quality of the situation,the greater the renovation potential".(4)By analyzing the core factors of cultivated land quality improvement,the key engineering of land consolidation is determined.According to the result of cultivated land quality potential,combined with regional functional characteristics and site conditions,the paper analyses the key factors of cultivated land quality promotion and determines the critical project.The key improvement factors of the cultivated land quality are the irrigation guarantee rate,drainage condition,road network density,highway accessibility,and the key engineering measures for land consolidation are road engineering and irrigation and drainage works in the Urban-rural Integrated Development Zone.The key improvement factors are the road network density,road accessibility,ladder state and ditch density,and the key engineering measures are highway engineering,farmland protection and ecological environment engineering in Industrial Transformation Oriented Zone.The key improvement factors are soil thickness,land evenness,land regularity,land link,irrigation guarantee rate,drainage condition,road network density,highway accessibility,and the key engineering measure,are land formation engineering,road engineering and irrigation and drainage works in Agricultural Land Remediation Oriented Zone.The key improvement factors are the state of ladder and the density of ditch,and the key engineering measures is farmland protection and ecological environment Preservation project to prevent soil erosion and protect ecological environment in Mountain ecological protection oriented zone.To sum up,based on the principle of differential land consolidation and the basic concept of service "Sansheng",this paper carries out the zoning of land consolidation function.And starting with the influence of land consolidation engineering measures on the quality of cultivated land,combined with the existing evaluation index system of cultivated land quality,the study constructs a set of cultivated land quality evaluation and potential calculation methods to serve the farmland improvement in mountainous and hilly areas.This method can improve the accuracy of evaluating the quality of cultivated land,and has strong practicability.Accurate identify the improvement factors of land improvement,determine the goal of improvement according to the regional functional characteristics and site conditions,and the potential of cultivated land quality improvement was calculated,which ensured the feasibility and authenticity.